Dan Mortensen (Dansound Inc), with arm up, demonstrates directional subwoofer techniques for PNW June meeting.
Dan Mortensen, owner of Dansound Inc. and PNW Section committee member, told of the modern implementations of directional subwoofer systems, and how various configurations of boxes can be made directional in certain ways. Instead of the common wisdom that lows are omnidirectional, they can be made directional for purposes such as noise ordinance compliance, reduced stage wash or reflections. His research utilized the free online Meyer Sound Labs MAPP speaker prediction calculator. He described and showed MAPP charts of directional subs configurations such as cardioid, endfire, Rat Sound Vortex, and others, in several different simulated situations such as on a hard concrete floor or elevated 100 feet high. There are quite a few configurations of custom configured boxes in use by sound companies.
After a refreshment break, door prizes awarded were:
AES USB memory sticks (from AES/Bob Moses): Jayney Wallick, Chris Deckard
DVD of AES-PNW meeting with the late Frank Laico: Bob Moses, Tyler Hovatter
Book, Musical Acoustics by Arthur Benade (courtesy Uneeda Audio): Dave Ellis
Continuing after the intermission, Section committee members Bob Smith and Daniel Casado assisted Dan with live demos and SMAART measurements of some configurations on the stage. Attendees could walk around the subs and confirm or deny the directionality and the measurement results. Audience member Ryan McCauley added many additional useful comments based on his work at McCauley Sound.
A special thanks goes to TJ Loehman of the ECA.
